Question

我一直在寻找一种方法来更改单词UITextView或"@"开头的"#"中的文本。我在下面的StackOverflow上找到了this code snippet，如果您键入"Hello"或"World"，则可以完美运行。

如何调整此代码，以便它可以检测到单词以“ @”或“＃”开头，后跟空格之前的任意数量的字符，并应用相同的样式？

如果用户以UITextView或"@"开头“单词”，则结果将导致"#"中文本的颜色发生变化。即：

棕色的 #fox 跳过了 @lazydog 。

func textViewDidChange(_ textView: UITextView) {
    let defaultAttributes = mediaDescription.attributedText.attributes(at: 0, effectiveRange: nil)
    let attrStr = NSMutableAttributedString(string: textView.text, attributes: defaultAttributes)
    let inputLength = attrStr.string.count
    let searchString : NSArray = NSArray.init(objects: "hello", "world")
    for i in 0...searchString.count-1
    {
        let string : String = searchString.object(at: i) as! String
        let searchLength = string.count
        var range = NSRange(location: 0, length: attrStr.length)

        while (range.location != NSNotFound) {
            range = (attrStr.string as NSString).range(of: string, options: [], range: range)
            if (range.location != NSNotFound) {
                attrStr.addAttribute(NSAttributedStringKey.foregroundColor, value: UIColor.red, range: NSRange(location: range.location, length: searchLength))
                attrStr.addAttribute(NSAttributedStringKey.font, value: UIFont(name: "Karla-Regular", size: 16.0)!, range: NSRange(location: range.location, length: searchLength))
                range = NSRange(location: range.location + range.length, length: inputLength - (range.location + range.length))
                textView.attributedText = attrStr
            }
        }
    }
}

Answer 1

假设您在文本中保留#或@，则可以修改Larme评论中的答案：

let regex = try! NSRegularExpression(pattern: "(?:#|@)\\w+", options: [])

func textViewDidChange(_ textView: UITextView) {
    let attrStr = NSMutableAttributedString(attributedString: textView.attributedText ?? NSAttributedString())
    let plainStr = attrStr.string
    attrStr.addAttribute(.foregroundColor, value: textView.textColor ?? .black, range: NSRange(0..<plainStr.utf16.count))

    let matches = regex.matches(in: plainStr, range: NSRange(0..<plainStr.utf16.count))

    for match in matches {
        let nsRange = match.range
        let matchStr = plainStr[Range(nsRange, in: plainStr)!]
        let color: UIColor
        if matchStr.hasPrefix("#") {
            color = .red
        } else {
            color = .blue
        }
        attrStr.addAttribute(.foregroundColor, value: color, range: nsRange)
    }

    textView.attributedText = attrStr
}

我只是更改了模式，以适应Swift 4.1，修复了一些错误，删除了一些冗余代码，并添加了一些代码来更改颜色。

UITextView / NSAttribute：检测单词是否以特定符号开头

1 个答案: